
\begin{tikzpicture}
  \coordinate[label=below:$A$] (A) at (-3,0);
  \coordinate[label=below:$B$] (B) at (2,0);
  \coordinate[label=above:$C$] (C) at (0,4);
  \coordinate[label=below:$D$] (D) at ($ (A)!.5!(B) $);
  \coordinate[label=left:$E$] (E) at ($ (C)!1/4!(D) $);
  \coordinate[label=right:$F$] (F) at ($ (C)!1/7!(B) $);
  \coordinate[label=right:$G$] (G) at ($ (B)!.5!(F) $);
  \fill[opafill=green] (C) -- (D) -- (G) -- cycle;
  \fill[opafill=yellow] (A) -- (B) -- (F) -- cycle;
  \draw (A) -- (B) -- (C) -- cycle (C) -- (D) (A) -- (F);
  \draw[dashed] (D) -- (G);
\end{tikzpicture}
